less juicy, and therefore have a poorer eating quality, than meat which is fatter and therefore less healthy. Health and palatability are to a degree incompatible, since the requirements for wholesomeness and eating quality are conflicting. It was mentioned that soft fat can be a problem in modern very lean pigs. This is because soft fat does not support the lean as effectively as firm fat and therefore may result in poorer muscle shape and less firm overall texture to the joint. However, softer fat contains a higher proportion of unsaturated fatty acids, which are healthier to eat. Again, one quality characteristic, appearance of the joint, is difficult to maintain while also achieving another, healthiness of the fat. A very effective way of improving carcass quality through reducing fatness is to use entire, rather than castrated, male animals, but the resulting lean meat may have less desirable eating qualities.
The problem of boar taint has been mentioned and there is a suggestion that beef from young bulls may be less tender than that from steers (Morgan et al., 1993).
Nitrite is used in the production of cured meats like ham and bacon (see Chapter 9). It reacts with the myoglobin to give the attrac- tive characteristic pink colour of these products. It also inhibits the growth of pathogenic bacteria like Clostridium, but the consumption of nitrite has been implicated in the potential development of some cancers. Nitrite therefore has both beneficial and potentially undesir- able characteristics as a meat additive.
Rapid carcass cooling inhibits the growth of microorganisms, so reducing potential spoilage, and also reduces weight losses by evapora- tion of water from the surface layers. However, cooling too rapidly may lead to less tender meat, either by reducing the activity of the naturally occurring proteolytic enzymes or by inducing cold shortening (see Chapter 8). There are thus both positive and negative consequences of rapid carcass chilling.
The third level also required the meat to have maximum attractiveness in terms of appearance, convenience and eating quality. It is likely that the first quality requirement, that of wholesomeness, would be agreed by all people. However, the choice of the second and third level requirements, while obviously desirable, would not necessarily be everyone’s. Neither would the order of importance, and it is likely that different people in the meat production-consumption chain would have different views. For the final consumer, eating quality is likely to be the second priority after wholesomeness.
Strategies for improving quality
The first requirement is to identify what needs to be improved. In the USA, extensive surveys of beef tenderness (Morgan et al., 1991) and pork quality (Cannonet al., 1996) have been carried out to identify and prioritize problems. An essential output from such surveys is an estimate of the economic cost of the problems, allowing an assessment to be made of the cost of improvement in relation to the probable benefits. Of the many aspects of meat quality, some are easier to improve than others. Characteristics that are dependent on, and amenable to, human intervention can be controlled much more easily than those characteristics that are determined principally biologically.
Examples of the first type are safety and wholesomeness. These can be achieved by careful control of hygiene during production and prepara- tion. An example of the second type, which is much harder to control, is carcass fatness. We do not understand why there is variation in this largely because of the complexity of biological systems. We can reduce overall fatness in populations of animals by careful selection but we do not know how to reduce the variation. So, although the backfat thick- ness of pig carcasses has been very effectively reduced over the last 20 years (at an average rate of nearly 0.4 mm per year in the UK), there are still some carcasses that are too fat or too lean. This kind of variation extends to marbling fat, colour of the lean, WHC and eating quality.
The inherent, uncontrollable variation will always be likely to lead to a proportion of carcasses or joints that have unacceptable quality.
Unfortunately, modern consumers have come to expect uniformity of product. At a level of about 5% of unacceptable product, consumers begin to be prejudiced against repeat purchases – they tend not to buy the product again. An approach to this problem of inherent variation is to try and reduce it as much as possible by strict control of all factors thought to influence it and then to monitor quality carefully to identify that product which is unacceptable. This product can then be marketed differently. For example, potentially tough meat would go for
‘restructuring’. This could take the form of grinding, mincing or flaking
it, and reforming the comminuted meat into burgers or restructured steaks (see Chapter 8).
In the UK in the 1990s, the Meat and Livestock Commission intro- duced ‘Blueprints’ to improve the eating quality of pork, beef and, later, lamb. These specified procedures for breed selection, rearing, husbandry, handling and slaughter of the live animal, and post-mortem handling of the carcasses and meat, which had been identified as optimal based on available knowledge. By optimizing each stage in the production chain, the resulting meat quality would on average be enhanced. Warkup (1993) described this approach and also provided evidence of its effectiveness. Pork produced using the blueprint was on average rated more tender, and less variable in texture, by a taste panel than that purchased from normal retail sources. The latter pork could have included samples produced according to some parts of the blueprint specification so it was not a true control sample. The improve- ments shown in texture were therefore possibly conservative.
It is important to note that there are inherent costs to quality improvement. There is the cost of controlling the factors that are thought to influence quality, the cost of measuring or monitoring quality, and the cost of the product that does not conform to the desired quality. The latter is both because of the cost of not being able to sell the product for its original purpose and the cost of reprocessing it.
Quality assurance schemes
The object of these is to certify that particular standards have been followed in the production of meat. Their purpose is to give consumers confidence in buying meat produced under the particular scheme, and to counter the confusion and concern that sometimes arises from general criticisms levelled at some production methods or aspects of quality. Because they are addressed to consumers, they focus on aspects perceived to be of major importance to them. There are three main areas: food safety and wholesomeness, ethical quality, and sensory or eating quality. Food safety concerns revolve, for example, around the possible presence of antibiotic residues, pathogenic bacteria and the contribution to a healthy diet. Ethical concerns include both animal welfare and environmental issues such as pollution from waste products and fertilizers. Sensory concerns include undesirable meat colour and texture. The aim of the quality assurance scheme is to guarantee to the consumer that these concerns are unfounded.
There is variation between different schemes in terms of what quality aspects are included or emphasized. Often, these are related to the potential concerns of the consumers in the target market, whether home or export. In the UK, considerable emphasis is placed on animal
welfare. A quality assurance scheme originated by the Royal Society for the Prevention of Cruelty to Animals (RSPCA), and implemented through the company, Freedom Foods, specifies welfare standards for animals on the farm and through to slaughter. For example, in the standards for pigs, stalls and tethers are not allowed for dry sows (those without piglets). Piglets must not be weaned from their mothers before they are 3 weeks old, animals must be kept in stable social groups and have minimum areas to live in, and have access to straw. There must be no castration of male pigs if slaughtered at less than 90 kg live weight. Tail docking is prohibited except in certain circumstances and with the agreement of a veterinary surgeon. There must be a veterinary health plan. Pigs cannot be sold through live auction markets and must be slaughtered at the abattoir closest to the farm. Maximum transport times, and maximum times without food, are defined, and humane slaughter procedures specified.
Sometimes schemes relate to only one or two of the meat species and may focus on meat from stock in particular geographical regions.
Farm Assured British Pigs (Gready, 1997; Webb, 1998), Farm Assured Scotch Livestock (Simpson, 1993) for lamb and beef, and Premium Quality Welsh Lamb (Zalick, 1993) are examples. In North America, the Pork Quality Assurance (PQA) programme was developed by The National Pork Producers Council (Lautner, 1997). In one sense the existence of different schemes might be considered undesirable in that a single, all-embracing scheme would be simpler for the con- sumer to understand. An element of standardization is, in any case, desirable. An essential aspect of all quality assurance schemes is monitoring compliance with the set standards and auditing them effectively. Obviously too, it is important that these functions should be performed by assessors who are independent of the scheme. A useful overview of quality assurance schemes is given in Woodet al.
(1998).
Labelling and preconceptions
People may have preconceptions of the quality of certain products and this can influence the way they perceive the inherent or actual quality.
An example of this is the interest, in some European countries particularly, in meat from animals reared non-intensively. Sometimes this is associated with the notion of ‘organic’ food. Organically grown food is produced with minimal or no use of ‘chemical’ fertilizers, pesticides, pharmaceutical products or medicines. Non-intensive rear- ing systems and organic methods of production are perceived by many people to be in the best interests of the animal and to lead to better quality of the product. The former is often probably true but the latter
may not be. However, if meat is labelled as organically produced some consumers may be persuaded to believe that it will taste better, especially if, for ethical or other reasons, they normally buy meat from extensively or organically reared animals.
This effect is illustrated by the findings of a Dutch experiment. In the Netherlands some pigs are produced under a free-range, organic system (the animals are known as ‘Scharrelvarkens’). It is prescribed that the animals must be kept in groups, sows must have access to the open air and that their diet must contain 10% roughage but no anti- biotics or growth promoters, for example. This system is perceived to be beneficial to the welfare of the pigs and to produce better pork.
Packs of this pork were compared with equivalent packs of pork but derived from pigs reared in the normal, commercial, intensive system.
The pork was assessed by two groups of consumer. One comprised general members of the public, the other, people who normally preferred to buy meat from extensively reared animals. When the two sorts of pork were presented unlabelled to the consumers, practically no differences were detected by either consumer group. When the trial was repeated, but with the packs labelled as coming either from
‘normal’ or extensively reared pigs, the general public still did not detect material differences. However, the people who normally bought pork from extensively reared animals recorded very significant improved eating quality in this meat, but the results of the first trial with unlabelled packs had shown that there were really no inherent differences in quality between the two types of pork. The implication is that the consumers who normally bought meat from extensively reared animals had unwarranted preconceptions about its palatability and their assessments reflected these. Because they expectedthe meat to taste better they persuaded themselves that it actuallydid. This is an example of a general phenomenon. Delizaet al.(1996) have shown that consumers change their rating of the sweetness and bitterness of pure solutions of sucrose or quinine after being given (erroneous) informa- tion about them which led to expectations that the solutions were more or less sweet or bitter than they really were.